Management of flexible grid and supercarriers in optical networks using a data model

ABSTRACT

A controller includes a processor; and memory storing instructions that, when executed, cause the processor to obtain measurements of optical spectrum from an Optical Power Monitor (OPM) connected to a fiber having thereon, one or more optical signals from one or more optical transmitters, wherein the optical signals are based on a flexible grid, manage the one or more optical signals utilizing a first model and manage attenuation control granularity of a Wavelength Selective Switch (W SS) connected to the fiber utilizing a second model, and configure one or more of the W SS and the one or more optical transmitters based on the first model and the second model.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present patent/application is a continuation of U.S. patentapplication Ser. No. 16/205,528, filed Nov. 30, 2018, and entitled“MANAGEMENT OF FLEXIBLE GRID AND SUPERCARRIERS IN OPTICAL NETWORKS USINGA DATA MODEL,” which is a continuation of U.S. patent application Ser.No. 15/944,892, filed Apr. 4, 2018 (now U.S. Pat. No. 10,200,770 B2which issued on Feb. 5, 2019), and entitled “MANAGEMENT OF FLEXIBLE GRIDAND SUPERCARRIERS IN OPTICAL NETWORKS USING A DATA MODEL,” which claimspriority to Indian Patent Application 201711012653, filed Apr. 7, 2017,and entitled “MANAGEMENT OF FLEXIBLE GRID AND SUPERCARRIERS IN OPTICALNETWORKS USING A DATA MODEL,” the contents of each are incorporated byreference herein.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to optical networks systems andmethods. More particularly, the present disclosure relates to managementof flexible grid and supercarriers in optical networks using a datamodel (also known as an object model, information model, etc.).

BACKGROUND OF THE DISCLOSURE

Before the advent of flexible grid and supercarriers in opticalnetworks, optical channels were assigned to a center frequency and fixedwidth (e.g., based on the ITU grid—195 THz, 50 GHz width). The flexiblegrid allows the assignment of an arbitrary amount of optical spectrumfor channels (e.g., an arbitrary and flexible amount of spectrum).Supercarriers include a plurality of optical channels in a contiguousamount of spectrum with little or no guard bands between channels. Forexample, supercarriers can be routed in the optical network between thesame ingress and egress points. The conventional fixed grid approach issimplistic from an Operations, Administration, Maintenance, andProvisioning (OAM&P) perspective, namely each optical channel can bemanaged by its channel assignment slot (i.e., center frequency +fixedwidth). With the drive to flex grid, supercarriers, and coherent modems,there is a need for a different approach.

Typically, electrical frames are mapped into one or more opticalcarriers, and the data model which is used to manage the underlyinghardware is associated with the optical port, referred to as an OpticalChannel (OCh). As described herein, a data model is used by a managementsystem to perform OAM&P functions on underlying hardware. By associatingthe OCh with a physical port, a strong relationship is formed with thesupporting optical carriers. For instance, a 100G channel could beQuadrature Phase Shift Keying (QPSK) with a baud rate of about 35 Gbpsor a 16-Quadrature Amplitude Modulation (QAM) with half the baud rate ofthe QPSK carrier. In the conventional approach, there was some baseassumption between a physical port and the associated carrier (e.g.,10GE-LR4). However, as speeds increase on OCh, this relationship isharder to maintain.

Progress in high-speed electronics, especially in Digital-to-AnalogConverters (DACs) and Analog-Digital Converters (ADCs), is allowingcoherent optical modems to send symbol rates significantly higher thanthe 35 GBaud example above. One of the most popular and widely deployedrealizations of the ITU fixed grid channel plan is the 50 GHz grid wherechannels are spaced by 50 GHz from each other. Optical filtering isrequired to perform functions like optical switching at ReconfigurableOptical Add/Drop Multiplexer (ROADM) sites and the like, which meansthat not all of the 50 GHz channel is usable by the optical signals.This results in a maximum practical symbol rate which can be supportedby this channel plan which is less than 50 GBaud. Modems are currentlybeing contemplated for these networks with symbol rates in excess of 50GBaud and in the future higher symbol rates are expected to becomepractical. Therefore, the 50 GHz fixed grid is not sufficient goingforward, nor is there a fixed grid which will efficiently accommodateall future generations of modems. The flexible grid allows for theallocation of the appropriate amount of spectrum for all applicationswith a minimum of loss of spectral efficiency.

With respect to supercarriers, logically these are considered a singleunit from an OAM&P perspective. However, in practical networkapplications and with ever increasing speeds, it is expected thesupercarrier will be decoupled and not maintain a convenientrelationship with its associated underlying optical carriers.

BRIEF SUMMARY OF THE DISCLOSURE

In an embodiment, a method of managing an optical service in a nodeutilizing a flexible grid for optical spectrum includes utilizing aMedia Channel (MC) model to manage a portion of optical spectrum on anoptical line, the MC model includes first frequency information whichdefine the portion of optical spectrum; utilizing a Network MediaChannel (NMC) model to manage the optical service and to model a path ofthe optical service in the MC model, the NMC model includes secondfrequency information and port connection information for the opticalservice; and programming hardware in the node based on the MC model andthe NMC model to implement the optical service. The MC model can have aplurality of NMC routed therein each with its own NMC model. The MCmodel can be a Trail Termination Point (TTP). The NMC model can includetwo models with a first model to model a port for the optical serviceand a second model to model a path of the optical service in the MCmodel. The first model can be a Connection Termination Point (CTP) andthe second model can be a Cross Connection (CRS). The optical line canbe an Optical Multiplex Section and there can be one or more MC modelsfor the optical line. The MC model can have one or more NMC modelsrelated thereto for associated optical services in an MC associated withthe MC model. The method can further include utilizing a connectionfunction model to manage cross-connection between MC models and/or NMCmodels.

In another embodiment, a node configured to manage an optical service inan optical network utilizing a flexible grid includes one or moreoptical ports connected to physical layer components; and a controllerconfigured to utilize a Media Channel (MC) model to manage a portion ofoptical spectrum on an optical line, the MC model includes firstfrequency information which define the portion of optical spectrum,utilize a Network Media Channel (NMC) model to manage the opticalservice and to model a path of the optical service in the MC model, theNMC model includes second frequency information and port connectioninformation for the optical service, and program the one or more opticalports and/or the physical layer components based on the MC model and theNMC model to implement the optical service.

In a further embodiment, a non-transitory computer-readable storagemedium comprising instructions that, when executed, cause a processor toperform the steps of utilizing a Media Channel (MC) model to manage aportion of optical spectrum on an optical line, the MC model includesfirst frequency information which define the portion of opticalspectrum; utilizing a Network Media Channel (NMC) model to manage theoptical service and to model a path of the optical service in the MCmodel, the NMC model includes second frequency information and portconnection information for the optical service; and programming hardwarein the node based on the MC model and the NMC model to implement theoptical service.

In another further embodiment, a method of managing optical services ina node utilizing a flexible grid includes utilizing a Media Channel (MC)Trail Termination Point (TTP) to model frequency allocation of a MC onthe node; utilizing a Network Media Channel (NMC) Connection TerminationPoint (CTP) to model a specific port for an optical channelcorresponding to the NMC; utilizing a NMC cross connection (CRS) tomodel a path of the NMC in the MC; and programming hardware in the nodebased on the MC TTP, the NMC CTP, and the NMC CRS. The MC TTP canallocate bandwidth in physical media including a Wavelength SelectiveSwitch (WSS) passband with provisions for deadbands to account for rolloff in the WSS. The NMC CTP can model termination points as one offiltered ports and unfiltered ports for the optical channel. The NMC CRScan further model a frequency assignment of the NMC. The method canfurther include utilizing an NMC Controller (NMCC) object and SpectrumShape Control (SSC) object for control of the optical channel with thehardware. The NMCC can be aligned to optical spectrum of the NMC whichdoes not necessarily align to control granularity of the hardware andwherein the SSC is aligned to the control granularity of the hardware.The programming can utilize the NMCC and the SSC for control of thehardware and the MC TTP, the NMC CTP, and the NMC for allocation of theoptical channel through the hardware. The method can further includeutilizing a control plane object for modeling the NMC as a routed entityin a control plane. The method can further include utilizing a VirtualConnection Point (VCP) as a termination point to aggregate multiplehardware modules into one or more MCs. The method can further includeutilizing a Flexible Cross Connect (FCC) to manage connectivity to theNMC CTP.

In another further embodiment, an apparatus configured to manage opticalservices in a node utilizing a flexible grid includes circuitryconfigured to utilize a Media Channel (MC) Trail Termination Point (TTP)to model frequency allocation of a MC on the node; circuitry configuredto utilize a Network Media Channel (NMC) Connection Termination Point(CTP) to model a specific port for an optical channel corresponding tothe NMC; circuitry configured to utilize a NMC cross connection (CRS) tomodel a path of the NMC in the MC; and circuitry configured to programhardware in the node based on the MC TTP, the NMC CTP, and the NMC CRS.The MC TTP can allocate bandwidth in physical media including aWavelength Selective Switch (WSS) passband with provisions for deadbandsto account for roll off in the WSS. The NMC CTP can model terminationpoints as one of filtered ports and unfiltered ports for the opticalchannel. The NMC CRS can further model a frequency assignment of theNMC. The apparatus can further include circuitry configured to utilizean NMC Controller (NMCC) object and Spectrum Shape Control (SSC) objectfor control of the optical channel with the hardware. The NMCC can bealigned to optical spectrum of the NMC which does not necessarily alignto control granularity of the hardware and wherein the SSC is aligned tothe control granularity of the hardware. The programming can utilize theNMCC and the SSC for control of the hardware and the MC TTP, the NMCCTP, and the NMC for allocation of the optical channel through thehardware. The apparatus can further include circuitry configured toutilize a control plane object for modeling the NMC as a routed entityin a control plane.

In another further embodiment, a node configured to manage opticalservices in an optical network utilizing a flexible grid includes one ormore optical ports; a Wavelength Selective Switch (WSS) coupled to theone or more optical ports; and a controller configured to utilize aMedia Channel (MC) Trail Termination Point (TTP) to model frequencyallocation of a MC on the node, utilize a Network Media Channel (NMC)Connection Termination Point (CTP) to model a specific port for anoptical channel corresponding to the NMC, utilize a NMC cross connection(CRS) to model a path of the NMC in the MC, and program the one or moreoptical ports and the WSS based on the MC TTP, the NMC CTP, and the NMCCRS. The MC TTP can allocate bandwidth in physical media including aWavelength Selective Switch (WSS) passband with provisions for deadbandsto account for roll off in the WSS.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated and described herein withreference to the various drawings, in which like reference numbers areused to denote like system components/method steps, as appropriate, andin which:

FIG. 1 is a block diagram of a network illustrating physical layercomponents in a Contentionless, Directionless, Colorless (CDC) flexiblegrid ROADM;

FIG. 2 is a network diagram of the network of FIG. 1 illustrating MediaChannel (MC) Trail Termination Points (TTPs) (MC-TTPs);

FIG. 3 is a network diagram of the network of FIG. 1 illustratingNetwork Media Channel (NMC) Connection Termination Points (CTPs)(NMC-CTPs);

FIG. 4 is a network diagram of the network of FIG. 1 illustrating NMCcross-connections 24;

FIG. 5 is a block diagram of an Optical line Trail Termination Point(TTP);

FIG. 6 is a block diagram of an Optical line Connection TerminationPoint (CTP);

FIG. 7 is a block diagram of an MC CTP;

FIG. 8 is a block diagram of an NMC terminated CTP (tCTP);

FIG. 9 is a block diagram of a Virtual Connection Point (VCP);

FIG. 10 is a facility model with no MCs or NMCs;

FIG. 11 is a facility model with MCs cross-connected through to a VCP;

FIG. 12 is a facility model with terminated MCs;

FIG. 13 is a facility model with mux/demux drop ports;

FIG. 14 is a facility model of VCPs;

FIG. 15 is an amplifier configuration with two line facility models;

FIG. 16 is a thin OADM configuration with pass-thru MCs;

FIG. 17 is a thin OADM configuration dropping NMCs to different muxes;

FIG. 18 is a thin OADM configurations dropping NMCs to the same mux.

FIG. 19 is a group OADM configuration with pass-thru MCs;

FIG. 20 is a group OADM configuration dropping NMCs to different muxes;

FIG. 21 is a group OADM configuration dropping NMCs to the same mux;

FIG. 22 is a submarine OADM configuration with pass-thru MCs;

FIG. 23 is a submarine OADM configuration dropping NMCs to adjacentgroups;

FIG. 24 is a submarine OADM configuration dropping NMCs to non-adjacentgroups;

FIG. 25 is a reconfigurable OADM (ROADM) configuration;

FIG. 26 is a direction independent OADM configuration;

FIG. 27 is a broadcast OADM configuration;

FIG. 28 is a CDC (contention-less, direction-less, and color-less)configuration;

FIGS. 29A-29E are network diagrams of separate MCs for NMCs terminatingat different nodes;

FIGS. 30A-30E are network diagrams of separate MCs for NMCs terminatingat different nodes in a redial scenario from the example of FIGS.29A-29E;

FIGS. 31A-31E are network diagrams of a single MC for NMCs sharing asame portion of the network;

FIGS. 32A-32E are network diagrams of a single MC for NMCs sharing asame portion of the network in a redial scenario from the examples ofFIGS. 31A-31E;

FIGS. 33A-33E are network diagrams of a single MC for SNP/SNCs;

FIGS. 34A-34E are network diagrams of a single MC for SNP/SNCs in aredial scenario from the example of FIGS. 33A-33E;

FIGS. 35A-35E are network diagrams of a separate VCP for SNP and SNC;

FIGS. 36A-36E are network diagrams of a separate VCP for SNP and SNC ina redial scenario from the example of FIGS. 35A-35E;

FIGS. 37A-37E are network diagrams of nested MCs;

FIGS. 38A-38E are network diagrams of nested MCs in a redial scenariofrom the example of FIGS. 37A-37E;

FIGS. 39A-39E are network diagrams of nested MCs with separate VCPs;

FIGS. 40A-40E are network diagrams of nested MCs with separate VCPs in aredial scenario from the example of FIGS. 39A-39E;

FIG. 41 is a network diagram illustrating relationships between thevarious models;

FIG. 42 is a network diagram of a new L0 (Layer 0) Control Plane (CP)Flex Grid service provisioning model;

FIG. 43 is a network diagram of an example network with variousinterconnected nodes;

FIG. 44 is a block diagram of an example node for use with the systemsand methods described herein;

FIG. 45 is a block diagram of a controller to provide control planeprocessing and/or operations, administration, maintenance, andprovisioning (OAM&P) for the node of FIG. 44, and/or to implement aSoftware Defined Networking (SDN) controller; and

FIGS. 46A-46F are network diagrams of an end-to-end service in a flexgrid network utilizing the various objects described herein.

DETAILED DESCRIPTION OF THE DISCLOSURE

In various embodiments, the present disclosure relates to management offlexible grid and supercarriers in optical networks using a data model.Again, the data model is used for various OAM&P purposes includingprogramming underlying hardware and enabling network operators to managetheir optical spectrum. As described herein, a Network Media Channel(NMC) is the bandwidth corresponding to the spectral width of an opticalsignal and a Media Channel (MC) is the spectral allocation in the mediumwhich encompasses one or more NMCs and any imposed excess spectrum foroptical filter penalties (e.g., filter roll-off), excess spectrum forfuture growth, etc. Multiple NMCs that support a single digital carrierare known as a supercarrier. The data model described hereinconceptualizes these entities in a similar manner as cross-connects,namely hardware at a Reconfigurable Optical Add/Drop Multiplexer (ROADM)node that puts NMCs into a MC is conceptually performing cross-connectsof the optical signals. Specifically, the systems and methods describedherein recognize that a supercarrier has nothing to do withelectrically-framed signals, but rather is a collection of opticalcarriers all with the same all-optical (OOO) source-destination (A-Z)demand pattern. The paths of the individual carriers may be constrainedto varying degrees to be the same or similar to each other depending onthe capabilities of the optical and digital hardware. Parameters thatcould be constrained include the difference between the carriers'frequencies, differential path length, etc., mainly concerned withlimiting the skew, or difference in delay between the carriers of thesupercarrier. Other constraints may be imposed based on operationalconcerns such as using same path for availability concerns, orcontiguous frequency slots for operational simplicity, etc.

The systems and methods provide a scheme to effectively model and managethe optical spectrum by using related and unrelated optical signals. Thesystems and methods enable a granular MC width assignment, support MCchanges throughout a path, manage NMCs as non-hierarchical entities withrespect to MCs, and use of the NMC as the entity which defines the pathand spectral assignment of a signal. With this approach, the systems andmethods allow separation of optical control granularity and modemspectrum assignment. The systems and methods can be implemented in acontrol plane or the like allowing selective use of flexible gridassignment capabilities.

The data model described herein enables more efficient use of opticalspectrum between common ingress-egress (A-Z) points regardless of thepurpose. Further, if an MC needs to be segmented, reassigned, orcoalesced, it does not require a redefinition of the NMC although NMCretuning may be required. The data model allows MCs to change throughoutthe network since the NMCs are routed entities, and this can providebetter filter performance.

The data model creates an approach in which control and spectrumallocation are separated allowing the maximum spectral efficiency acrosssubsequent generations of optical modem technology which may havedifferent non optical-granularity defined widths, etc. The systems andmethods allow a control plane, Software Defined Networking (SDN)controller, management system, etc. an opportunity to take advantage ofthe spectral efficiency benefits and spectrum flexibility.

As described herein, the data model (which may also be referred to as anobject model, information model, etc.) includes computer data in aspecified structure. The computer data is used to maintain and manageconfigurations of optical channels and to program and configure thephysical hardware associated with the optical network. The physicalhardware can include, for example, Wavelength Selective Switches (WSSs),ROADMs, tunable filters, multiplexers/demultiplexers, optical modems,etc. The computer data is further used by management systems (e.g.,controller on a network element, a control plane, SDN controller,Network Management System (NMS), Element Management System (EMS), etc.)for performing various OAM&P functions, such as the optical control andmodem configuration. An aspect of the data model is to enable managementinteroperability between disparate vendors. By introducing the conceptof technology-independent management, it is possible to performmanagement of diverse equipment using common communication interfaces.In this manner, a a high level view over a set of network elements canbe achieved. An example of a data model is described in ITU-TRecommendation M.3100 “Generic network information model,” (April/05),the contents of which are incorporated by reference.

Again, the data model herein further disassociates (from theconventional approach which specifies center frequency and width) theNMC from an optical signal. Instead of specifying a wavelength (e.g., adefined channel on the ITU grid or a center frequency), the NMC in afirst data model can only declare the required bandwidth (for a physicalport with one or more optical carriers) and the wavelength or spectrumis not assigned. A second data model provides the spectrum between anoptical ingress and egress point (e.g., on ROADM nodes). The second datamodel is responsible for defining and creating the MC and all NMCswithin it. The second data model may include restrictions that all NMCsshare some characteristics. Some of the restrictions may be hardwarelimitations imposed at the Optical Tributary Signal (OTSi) layer. Otherrestrictions may be imposed at this layer also, but have likely more todo with operational considerations. With these two data models, it ispossible to create arbitrary superchannels (i.e., MCs) of NMCs andmanage the spectrum of the MCs independently of the NMCs. There may beadditional data models, and the associated data models can have anassociation to an Optical Tributary Signal (OTSi).

The present disclosure provides a data model (i.e., object model,information model, etc.) for flexible grid which can be used in multiplenetwork topologies to implement the flexible grid as outlined in ITU-TRecommendation G.872 “Architecture of optical transport networks,”(January/17), the contents of which are incorporated by reference. Thedata model provides a concise approach to accommodate many topologiesand implementations for fixed grid systems, flexible grid systems (suchas ROADM/WSS-based), broadcast networks, etc. Note, the use of the datamodel with the fixed grid (i.e., existing Dense Wave DivisionMultiplexing (DWDM) deployments) is important for backward compatibilitysuch as during upgrades to the flexible grid as well as forinterconnection to systems that do not support flexible grid.

With the approach described herein, modeling of the physical port nowincludes a bandwidth descriptor. (Frequency can be assigned later).Ideally, it is not bound to the spectrum (e.g., MC or NMC). It may belimited to the colored mux/demux point, or it may be colorless (e.g.,Broadcast unit (BU)). It may include the wavelength (for backwardcompatibility).

If a single port emits more than 1 carrier, ideally each carrier'sbandwidth is specified and controllable. If the NMCs are notindividually specified but continuous, then the aggregate NMC may betreated as an opaque MC with the bandwidth of MC specified. This may(does not have to) drive the nesting of MCs within MC.

The modeling of the optical switching hardware is required. The WSSapplies dead bands (through filtering) when it switches; a CMX BU doesnot. This is very important and usually forces MC creation.

As part of path computation, an MC is defined for an all opticalsource-destination path that traverses the ROADM portion of the network.Optionally, it may be extended into the non-ROADM portion of thenetwork. If no such all optical A-Z exists, then a new one is created.As part of path computation, optical carriers (NMC) attempt to reuseexisting MCs. The MC may grow to accommodate a new request (start orstop frequency) or reuse a bit of unused spectrum within the MC so longas it satisfied the NMC BW requirements. (e.g., the ROADM's WSS BWallocation (n * granularity) ideally never matches the NMC BWrequirements.)

Once the all optical path is computed then the NMC is assigned a centerfrequency and width or start and stop frequency (could use wavelength).One of the tasks of validation, performed either at the network elementor at a controller layer, is to ensure that the assigned width is equalto or greater than the required width set at the NMC-CTP end points ofthe cross connect. Service attributes are assigned to co-route NMC thatmust travel along the same path. Additional attributes may indicatemaximum frequency differential (differential delay due to non-alignedfrequencies may exceed 10+μs—important for the receiver, and in somecases important to the transmitter).

Electrical regeneration is just at the edge of the scope of the datamodel in that the signals would terminate in an NMC-CTP and re-enter thenetwork at a different NMC-CTP. This function could be used in the casethat a signal needed to be regenerated due to propagation penalties, orchange frequencies for some reason, e.g. spectral blocking. Frequencyreassignment in the optical domain, though not practical in commercialsystems today, may be a possibility in the future. The result may be achange in the optical signal's frequency, i.e., the NMC requirements, atsome point in the path. An NMC frequency interchange function in theoptical layer would be a way to achieve this in the model wherein, in acapable device, the NMC-CRS would have a different source anddestination center frequency and/or width.

The NMCs using an MC may not share the same MC source or destinationnode. This is especially true for truly gridless (colorless) nodes thataggregate NMCs but do not drive MC creation (dead band) due to theunderlying technology (e.g., a branching unit used as a multi-nodeattachment to an ROADM). The MC may not be contiguous. Non-contiguous MClikely create an additional dead band and reduce ideal spectrum fill.Many MCs may be used between the all optical A-Z.

The system may allow no MC creation for a point-to-point ROADM-to-ROADM(single hop) MC. The real advantage of the multi-hop MC is that theintermediate MC nodes do not / cannot access the NMCs within the MCwithout damaging the MC. NMC sharing an MC need not be of the same type;a secondary system (optimization) may impose such a restriction.

Failure of the MC may signal “path tear” notifications to the NMCsource/destinations. Optionally, a second system (e.g. controller,control plane) may attempt to reinstall the MC. If the MC is notspectrally matched, NMC may need to retune. The MC may also break theoptical viability of the NMC. (Part of the MC may be restored).

FIG. 1 is a block diagram of a network 10 illustrating physical layercomponents in a Contentionless, Directionless, Colorless (CDC) flexiblegrid ROADM. Again, the data model described herein can be used todefine, manage, and configure the network 10. The network 10 includesmulti-degree ROADMs 12 which can be flexible grid WSS-based, CDCadd/drop multiplexers 14, and fibers 16. The fibers 16 include mediaacross the optical spectrum. Note, while the network 10 is illustratedas a CDC flexible grid ROADM-based implementation, the data model canalso be utilized in fixed wavelength add/drop, broadcast, etc. The datamodel can be implemented at a network element (NE) level where eachnetwork element is a collection of Optical Multiplex Section (OMS) andOptical Transport Section (OTS) groups, i.e., degrees and add/drops. Asa consequence, instances of list elements must be unique within the NE(i.e., across degrees and add/drops).

The following terminology is used herein for the data model:

Element Acronym Definition Media Channel MC A defined slice of opticalspectrum which can be packed with NMCs Network Media NMC The spectrumand path consumed by an Channel optical carrier Optical OTSi An opticalcarrier or set thereof tributary signal Physical PTP A physical pointassociated with the network Termination element where a fiber is pluggedinto Point Trail TTP A multiplexing point associated with theTermination network element where NMCs are Point added/dropped from anMC Connection CTP A point in the network element where Terminationsomething is cross connected, i.e., NMC to Point MC, etc. Virtual VCPSimilar to a CTP but provisioned for more Connection than one CTP -binds multiple NMC to VCP Point and VCP to MC Sub Network SNP An MC withadditional attributes Path

FIG. 2 is a network diagram of the network 10 illustrating MC TTPs 20.The MC-TTPs 20 monitor and terminate the MC from the line and coordinatethe MC towards the line. NMCs can be accessed at the back end of the MCTTP 20. In FIG. 2, for simplicity, the MC on the WSS line-facing portsare shown as the same on both ends of the fiber 16; although this is notrequired in the model, it simplifies this example. Also, for simplicity,the MC on either side of the middle ROADM node are shown as the same;this is also not required by the model, it simplifies the example andsimplifies routing. The MC TTP 20 can include various parameters such asa deadband, minimum frequency, and maximum frequency. With the MC TTP20, bandwidth in physical media (e.g., WSS passband) can beallocated/modeled with provisions for deadbands to account for filterroll-off. The MC TTP 20 is a new object model for flex grid and itdefines that start and stop of the MC. The entire spectrum is accessiblevia the NMCs from the back end of the MC TTP 20.

The MC TTP 20 models the frequency allocation (on any “grid” ifapplicable, e.g. ITU-872 “Flexible Grid” on 12.5 GHz granularity, fixedgrid, etc.), and the creation of an optical filter function associatedwith a port, e.g. a line port, which includes the definition of anyassociated deadband due to the optical filter function. The MC TTP 20not only models the filter function, but also the “wavelength blocking”behavior of the port in question since frequencies cannot be assigned tomore than one MC TTP 20 on the same port.

MCs are terminated by MC TTP 20 objects at line ports of OADM/ROADMnodes. In an example embodiment, the MC TTP 20 can be a data object asfollows:

+--rw mc-ttp* [name] | +--rw name string | +--rw supporting-entityinstance-identifier | +--rw min-freq THz | +--rw max-freq THz | +--rwmin-freq-deadband? GHz | +--rw max-freq-deadband? GHz | +--rwconnection-type? enumeration | +--ro paired-mc-ttp? string | +--ronmc-connections* string

The name must be unique. The supporting-entity is the identifier of theobject instance in a device specific model on which the MC is created,e.g., WSS port. The MC TTP 20 is characterized by min-freq and max-freq(rather than Center Frequency (Fc)/Spectral Width to supportasymmetrical resizing). Optionally, the MC TTP 20 can include distinctprovisionable deadband(s) associated with each of min-freq-deadband andmax-freq-deadband. The connection type, paired MC TTP, and NMCconnections are supporting entities for NMC connection points: nmc-ctpobjects.

MCs are not cross connected in this data model; they reflect only thephysical filtering characteristics of the ports with which they areassociated. The NMC is the “stitchable” entity as intended in ITU-TG.872. As such, the MCs which support an end-to-end NMC may havedifferent min-freq and max-freq along the path so long as the NMCfrequency requirements are met by each.

FIG. 3 is a network diagram of the network 10 illustrating NMC CTPs 22.The NMC CTPs 22 provide optional non-intrusive monitoring of the NMCwithin the MC. The NMC CTP 22 can provide a connection function to a VCPthen to another NMC. Note, the VCP can be optional. NMC CTPs 22 aretermination points for NMC cross connections, and the details of the NMCare modeled in the cross-connection objects. This allows for changes tothe NMC parameters independent of the connection point objects. Forexample, the frequency can be assigned at the cross-connection stagewithout re-defining the connection points. Retuning an NMC to adifferent center frequency or width can also be achieved withouttouching the termination points. In other words, the path can bemaintained independently of the choice of other parameters. The NMC CTP22 is also a new object for flex grid. The NMC CTP 22 is connected toanother line or to a drop port.

In an example embodiment, the NMC CTP 22 can be a data object asfollows:

+--rw nmc-ctp* [name] | +--rw name string | +--rw supporting-entityinstance-identifier

The supporting-entity is the identifier of the object instance on whichthe NMC is to be connected. Two cases exist for this connection-filteredor unfiltered ports. For filtered ports, the supporting-entity is an MCTTP 20 object, e.g., associated with a line or WSS port. For unfilteredports, the supporting-entity may be either an optional MC TTP or anobject instance in the device specific model, e.g. colorless add/dropport in a CD or CDC MUX/DeMUX structure (implied MC which includes theentire transmission band). In this case of an add or drop NMC CTP 22 (asdefined by the cross-connection), there will be an adjacent OpticalTributary Signal (OTSi)—1:1 OTSi to NMC relationship. At the centerROADM node 12, the NMC CTP 22 has no frequency information other thanthe association with a specific MC TTP.

FIG. 4 is a network diagram of the network 10 illustrating NMCcross-connections 24. The NMC cross-connections 24 (CRS NMC) define theimportant parameters of the NMCs such as path, frequency, etc. In anexample embodiment, the NMC cross-connection 24 can be a data object asfollows:

+--rw nmc-cross-connection* [name] +--rw name string +--rw frequency THz+--rw width GHz +--rw from-nmc-ctp −> /nmc-ctp/name +--rw to-nmc-ctp −>/nmc-ctp/name +--rw cktid? string +--rw connection-type? enumeration+--ro paired-cross-connection? −> /nmc-cross-connection/name +--roconnection-subtype? enumeration +--ro port-trail* string

The frequency is the center frequency. The connection-type allows forthe creation of uni-directional, paired uni-directional (driving thevalue in the paired-cross-connection object) or bi-directionalcross-connections. The connection-subtype allows for the designation ofADD, DROP or PASSTHROUGH connections.

Collectively, the NMC CTP 22 and the associated CRS NMC 24 model theNMCs. The NMC-CTPs 22 are associated to specific ports (for unfilteredports—e.g., colorless mux/demux inputs/outputs) and MC TTPs (for DWDM(filtered) ports, e.g., line ports) to be cross-connected. The CRS NMC24 models the cross connection of these ports for the frequencyassignment of that particular NMC. The approach described herein placesthe allocation of the frequency (which must be reserved from within theMC TTP 20 bandwidth excluding deadbands) within the CRS NMC 24 to allowfor the re-routing or re-tuning of the NMC without having to delete andre-create all NMC CTP 22. This is important for the control planeaspects using these data models.

In the prior art, the Optical channel cross-connections (CRS-OCh) havean implied bandwidth and center frequency due to the enumeration of afixed grid. All CTPs were implicit on all ports since there was never aneed to change them. The OCh in the prior art is equivalent to a 1:1MC:1NMC named by the center frequency. The approaches described hereincontemplate an in-service migration from fixed grid (OCh) to flex gridusing the data models. Also, the data models (MC, NMC) can be used tomatch the OCh in the prior art to support legacy interoperability.

FIGS. 5-9 illustrate block diagrams of various flex grid facilities inaddition to the MC TTP 20, the NMC CTP 22, and the CRS NMC 24. FIG. 5 isa block diagram of an Optical line TTP 26. The Optical line TTP 26monitors and terminates the incoming Optical Line as well as originatingthe outgoing Optical Line. NMCs and/or MCs can be accessed at the backend of the Optical line TTP 26.

FIG. 6 is a block diagram of an Optical line CTP 28. The Optical lineCTP 28 provides optional non-intrusive monitoring of the incomingOptical Line and can only be cross-connected to another Optical line CTP28. Generally, no access is provided to MCs or NMCs at the Optical lineCTP 28.

FIG. 7 is a block diagram of an MC CTP 30. The MC CTP 30 providesoptional non-intrusive monitoring of the MC from the Line and provides aconnection function to another non-terminated MC. Generally, no accessis provided to NMCs at the MC CTP 30. The MC CTP 30 can includeparameters such as minimum frequency, maximum frequency, a dead bandamount, etc. The MC CTP 30 provides the value of channel (NMC) agnosticpass through nodes when no traffic is being added/dropped within a MediaChannel. Similar to the MC TTP 20, the MC CTP 30 is a new object forflex grid when the MC is pass through transparently. The MC CTP 30provides a connection function to a VCP and then to anothernon-terminated MC.

FIG. 8 is a block diagram of an NMC terminated CTP (tCTP) 32. The NMCterminated CTP 32 monitors and terminates the NMC on the client drop andoriginates the NMC towards the line from the transceiver (or modem). TheNMC tCTP 32 provides a connection function to a VCP and then to anotherNMC. The parameters of the NMC tCTP 32 can include identification ofmux/demux ports, minimum frequency, maximum frequency, requiredbandwidth, etc. The NMC tCTP 32 is also a new object for flex grid wherethe NMC starts and stops-this CTP is connected to a line drop port.

FIG. 9 is a block diagram of a VCP 34. The VCP 34 provides a connectionfunction to NMCs or MCs and can be cross-connected to multiple NMC CTPs22 or MC CTPs 30. The NMC CTPs 22 can be cross-connected Line to Line orLine to Mux/Demux. The MC CTPs 30 can be cross-connected Line to Line.The VCP 34 has two directions, e.g., 0 and 1, and the VCP 34 needs tohave an equal number of cross-connects as the From endpoint and Toendpoint for each direction.

The VCP 34 is a logical connection point with no physical anchor (floatsin space) and that can span multiple shelves. The VCP 34 is atermination point of a SNC and supports line-line or line-add/dropconnections. The VCP 34 allows aggregation of multiple transponders anddefines the required spectral width independent of spectral allocationor path. The VCP 34 may be serviced by a single MC or multiplenon-contiguous MCs. Further, the VCP 34 is independent of any hardwareconfiguration.

The relationships between the foregoing models are as follows:

-   -   →Optical Line (e.g., Optical Multiplex Section (OMS))        -   Terminated at every node except amplifier nodes    -   →MC CTP 30        -   1:N relationship to Optical Line    -   →MC TTP 20        -   1:N relationship to Optical Line    -   →Nested MC (within MC)    -   MC:MC=1:N (may be nested within another MC)    -   →NMC CTP 22    -   Can exist directly within an optical line, 1:N relationship to        Optical Line    -   Can exist within an MC TTP 20, 1:N relationship to MC TTP20    -   →The NMC tCTP 32    -   Exists only on drop side of Mux/Demux    -   1:1 relationship to drop side channels

FIGS. 10-14 illustrate block diagrams of flex grid facility models. FIG.10 is a facility model 40 with no MCs or NMCs. The facility model 40 isused at amplifier nodes and has a line facility existing within theoptical line port. There is no visibility of MCs or NMCs in the facilitymodel 40.

FIG. 11 is a facility model 42 with MCs cross-connected through to a VCP34. The MC CTP 30 exists within the optical line port and the MC CTPs 30are cross-connected to other MC CTPs 30 within other optical line ports,via a VCP 34. The MC CTP 30 represents pass-thru bands or MCs.

FIG. 12 is a facility model 44 with terminated MCs. The MC TTPs 20 existwithin an optical line port, and the NMC CTPs 22 exist within an MC TTP20. The MCs are terminated, and the NMCs are cross-connected to otherNMC CTPs 22, via a VCP 34. The MC TTP 20 represents add/drop bands orMCs, and an NMC CTP 22 exists for each add/drop or pass-thru channel.

FIG. 13 is a facility model 46 with mux/demux drop ports. NMC tCTPs 32exist at the Mux/Demux drop port and are cross-connected to other NMCCTPs 22 within MCs, via VCPs 34. The NMC tCTPs 32 represent thetermination of the NMC where it enters/exits the photonic network.

FIG. 14 is a facility model 48 of VCPs 34. VCPs 34 exist betweencross-connected MC CTPs 30 or NMC CTPs 20.

FIGS. 15-29 illustrate equipment configuration examples where physicaloptical equipment is modeled with the facility models described herein.Those skilled in the art will recognize FIGS. 15-29 illustratenon-limiting examples of various equipment configurations using thevarious models described herein; other embodiments are alsocontemplated.

FIG. 15 is an amplifier configuration with two facility models 40. FIG.16 is a thin OADM configuration with pass-thru MCs. Here, CMDs aremuxes/demuxes and the equipment is modeled by the two facility models42. There is a VCP 34 and a FCC (Flexible Cross Connect) table showingexample slot numbers, port numbers, etc.

FIG. 17 is a thin OADM configuration dropping NMCs from the same SNCs todifferent muxes. There is a VCP 34 and a FCC (Flexible Cross Connect)table showing example slot numbers, port numbers, etc. FIG. 18 is a thinOADM configuration dropping NMCs to the same mux. There is a VCP 34 anda FCC (Flexible Cross Connect) table showing example slot numbers, portnumbers, etc.

FIG. 19 is a group OADM configuration with pass-thru MCs. There is a VCP34 and a FCC (Flexible Cross Connect) table showing example slotnumbers, port numbers, etc. FIG. 20 is a group OADM configurationdropping NMCs from the same SNC to different muxes. There is a VCP 34and a FCC (Flexible Cross Connect) table showing example slot numbers,port numbers, etc. FIG. 21 is a group OADM configuration dropping NMCsto the same mux. There is a VCP 34 and a FCC (Flexible Cross Connect)table showing example slot numbers, port numbers, etc.

FIG. 22 is a submarine OADM configuration with pass-thru MCs. There is aVCP 34 and a FCC (Flexible Cross Connect) table showing example slotnumbers, port numbers, etc. FIG. 23 is a submarine OADM configurationdropping NMCs to adjacent groups. There is a VCP 34 and a FCC (FlexibleCross Connect) table showing example slot numbers, port numbers, etc.FIG. 24 is a submarine OADM configuration dropping NMCs to non-adjacentgroups. There is a VCP 34 and a FCC (Flexible Cross Connect) tableshowing example slot numbers, port numbers, etc.

FIG. 25 is a reconfigurable OADM (ROADM) configuration. There is a VCP34 and a FCC (Flexible Cross Connect) table showing example slotnumbers, port numbers, etc. FIG. 26 is a direction independent OADMconfiguration. There is a VCP 34 and a FCC (Flexible Cross Connect)table showing example slot numbers, port numbers, etc. FIG. 27 is abroadcast OADM configuration. There is a VCP 34 and a FCC (FlexibleCross Connect) table showing example slot numbers, port numbers, etc.FIG. 28 is a CDC (contention-less, direction-less, and color-less)configuration. There is a VCP 34 and a FCC (Flexible Cross Connect)table showing example slot numbers, port numbers, etc.

FIGS. 29-40 illustrate examples of SNPs. Specifically, FIGS. 15-28illustrated equipment configuration examples at a single node whereasthe SNPs illustrate network examples. Again, those skilled in the artwill recognize FIGS. 29-40 present non-limiting examples forillustration purposes and other embodiments are also contemplated.

FIGS. 29A-29E are network diagrams of separate MCs for NMCs terminatingat different nodes. In FIG. 29A, the facility models, are illustratedfor node A, and NMC-1-11-1 exists within MC-1-11 and NMC-1-12-1 existswithin MC-1-12. In FIG. 29B, the facility models, are illustrated fornode B and MC-1-11 and MC-1-12 are cross-connected through the node B.In FIG. 29C, the facility models, are illustrated for node C, andMC-1-11 is terminated at the node C along with NMC-1-11-1 and MC-1-12 iscross-connected through the node C. In FIG. 29D, the facility models,are illustrated for node D, and MC-1-12 is cross-connected through thenode D. In FIG. 29E, the facility models, are illustrated for node E,and MC-1-12 is terminated at the node E, along with NMC-1-12-1.

FIGS. 30A-30E are network diagrams of separate MCs for NMCs terminatingat different nodes in a redial scenario from the example of FIGS.29A-29E. In FIG. 30A, at node A, there is a redial of the MCs from nodeB to node F. New MC TTPs and NMC CTPs are created on a new line. Thecross-connects within the FCC (Flexible Cross Connect) are changed touse the new NMC CTP on the line side for SNC-11 (Subnetwork Connection).The cross-connects within the FCC are changed to use the new NMC CTP onthe line side for SNC-12. In FIG. 30B, the nodes F, G are setup with theassociated facilities. In FIG. 30C, at node C, new MC TTPs, MC CTPs andNMC CTPs are created on a new line. The cross-connects within the FCCare changed to use the new NMC CTP on the line side for SNC-11. Thecross-connects within the FCC are changed to use the new MC CTP forSNC-12. In FIGS. 30D-30E, there are no facility changes at nodes D, E.

The FCC allows flexible provisioning of NMC and MC cross-connectionsthrough VCPs. The FCCs are associated uniquely with a VCP and define thelogical connections through it. The FCC connection can beuni-directional, paired uni-directional or bi-directional. Eachconnection is identified by a unique connection ID, each connection IDhas specified connections/terminations associated with opposingdirections of the VCP which can be provisioned independently. Aconnection is “complete” when connections/terminations on both sides ofthe VCP 34 are specified.

FIGS. 31A-31E are network diagrams of a single MC for NMCs sharing asame portion of the network. Specifically, there are two MCs, MC-1,MC-11 on different portions of the network and two different NMCs,NMC-1-11-1, NC-1-12-1, which have different destinations. In FIG. 31A,the facility models are shown for node A, and NMC-1-11-1 and NMC-1-12-1both exist within a common MC-1. In FIG. 31B, the facility models areshown for node B, and MC-1 is cross-connected through the node B. InFIG. 31C, the facility models are shown for node C, and MC-1 isterminated at the node C. The NMC-1-11-1 is dropped to a terminated NMCCTP, and the NMC-1-12-1 is cross-connected and now exists within MC-11.In FIG. 31D, the facility models are shown for node D, and the MC-11 iscross-connected through the node D. In FIG. 31E, the facility models areshown for node E, and the MC-1-12 is terminated at the node E, alongwith NMC-1-12-1.

FIGS. 32A-32E are network diagrams of a single MC for NMCs sharing asame portion of the network in a redial scenario from the examples ofFIGS. 31A-31E. In FIG. 32A, at node A, the new MC TTPs and NMC CTPs arecreated on a new line. The cross-connects within the FCC are changed touse the new NMC CTP on the line side for SNC-11. The cross-connectswithin the FCC are changed to use the new NMC CTP on the line side forSNC-12. In FIG. 32B, the nodes F, G are setup with the associatedfacilities. In FIG. 32C, at node C, new MC TTPs and NMC CTPs are createdon a new line. The cross-connects within the FCC are changed to use thenew NMC CTP on the line side for SNC-11. The cross-connects within theFCC are changed to use the new MC CTP for SNC-12. In FIGS. 32D-32E,there are no facility changes at nodes D, E.

FIGS. 33A-33E are network diagrams of a single MC for SNP/SNCs. In FIG.33A, the facility models are shown for node A. NMC-1-11-1 and NMC-1-12-1both exist within a common MC-1, and MC-1 is where the SNP begins, butthere is there is no “local endpoint.” This looks different in the nextset of network diagrams where there is a VCP which is the “localendpoint” which is not the MC TTP. In FIG. 33B, the facility models areshown for node B, and MC-1 is cross-connected through the node B. InFIG. 33C, the facility models are shown for node C. MC-1 is terminatedat NE C. There is no “remote endpoint” other than the MC TTP itself.NMC-1-11-1 is dropped to a terminated NMC CTP, and NMC-1-12-1 iscross-connected and now exists within MC-11. In FIG. 33D, the facilitymodels are shown for node D, and MC-11 is cross-connected through thenode D. In FIG. 33E, the facility models are shown for node E, andMC-1-12 is terminated at the node E, along with NMC-1-12-1.

FIGS. 34A-34E are network diagrams of a single MC for SNP/SNCs in aredial scenario from the example of FIGS. 33A-33E. In FIG. 34A, at nodeA, new MC TTPs and NMC CTPs are created on a new line. Thecross-connects within the FCC are changed to use the new NMC CTP on theline side for SNC-11. The cross-connects within the FCC are changed touse the new NMC CTP on the line side for SNC-12. Because the MC TTP wasused as the local endpoint for the SNP, then the local endpoint haschanged. In FIG. 34B, the nodes F, G are setup with the associatedfacilities. In FIG. 34C, at node C, new MC TTP s and NMC CTPs arecreated on a new line. The cross-connects within the FCC are changed touse the new NMC CTP on the line side for SNC-11. The cross-connectswithin the FCC are changed to use the new MC CTP for SNC-12. Because theMC TTP was used as the remote endpoint for the SNP, then that remoteendpoint has changed. In FIGS. 34D-34E, there are no facility changes atnodes D, E.

FIGS. 35A-35E are network diagrams of a separate VCP for SNP and SNC. InFIG. 35A, the facility models are shown for node A. NMC-1-11-1 andNMC-1-12-1 both exist within a common MC-1 terminated CTP. MC-1terminated CTP is cross-connected via a VCP to an MC CTP on the line.This VCP is the local endpoint for the SNP. In FIG. 35B, the facilitymodels are shown for node B, and MC-1 is cross-connected through thenode B. In FIG. 35C, the facility models are shown for node C. MC-1 iscross-connected to a terminated MC CTP where it is terminated at thenode C. This VCP is the remote endpoint of the SNP. NMC-1-11-1 isdropped to a terminated NMC CTP, and NMC-1-12-1 is cross-connected andnow exists within MC-11. In FIG. 35D, the facility models are shown fornode D, and MC-1-11 is cross-connected through the node D. In FIG. 35E,the facility models are shown for node E, and MC-1-12 is terminated atnode E, along with NMC-1-12-1.

FIGS. 36A-36E are network diagrams of a separate VCP for SNP and SNC ina redial scenario from the example of FIGS. 35A-35E. In FIG. 36A, atnode A, a new MC CTP for the SNP is created on a new line. Thecross-connects within the FCC for the SNP are changed to use the new MCCTP on the line side. The local endpoint for the SNP does not change andthere is no change to any SNCs. In FIG. 36B, the nodes F, G are setupwith the associated facilities. In FIG. 36C, at node C, a new MC CTP forthe SNP is created on a new line. The cross-connects within the FCC forthe SNP are changed to use the new MC CTP on the line side. The SNPremote endpoint does not change, and there is no change to any SNCs. InFIGS. 36D-36E, there are no facility changes at nodes D, E.

FIGS. 37A-37E are network diagrams of nested MCs. In FIG. 37A, thefacility models are shown for node A. NMC-1-11-1 exists within MC-1-11and NMC-1-12-1 exists within MC-1-12. MC-1-11 and MC-1-12 both existwithin a common MC-1 which exists for the SNP. MC-1 is where the SNPbegins, but there is no “local endpoint” other than the MC TTP itself.In FIG. 37B, the facility models are shown for node B, and MC-1 iscross-connected through the node B. In FIG. 37C, the facility models areshown for node C. MC-1 is terminated at an MC TTP. MC-1 is where the SNPends, but there is no “remote endpoint” other than the MC TTP itself.MC-1-11 and MC-1-12 both exist within MC-1. MC-1-11 is terminated andNMC-1-11-1 is cross-connected to a drop port. MC-1-12 CTP iscross-connected to another MC CTP on another line. In FIG. 37D, thefacility models are shown for node D, and MC-1-11 is cross-connectedthrough the node D. In FIG. 37E, the facility models are shown for nodeE, and MC-1-12 is terminated at the node E, along with NMC-1-12-1.

FIGS. 38A-38E are network diagrams of nested MCs in a redial scenariofrom the example of FIGS. 37A-37E. In FIG. 38A, at node A, new MC TTPsand MC CTPs are created on a new line. The cross-connects within theFCCs for SNC-11 are changed to use the new NMC CTP on the line side. Thecross-connects within the FCCs for SNC-12 are changed to use the new NMCCTP on the line side. Because the MC TTP was used as the local endpointfor the SNP, then that local endpoint has changed. In FIG. 38B, thenodes F, G are setup with the associated facilities. In FIG. 38C, new MCTTPs, MC CTPs and NMC CTPs are created on a new line. The cross-connectswithin the FCCs for SNC-11 are changed to use the new NMC CTP on theline side. The cross-connects within the FCCs for SNC-12 are changed touse the new MC CTP on the line side. Because the MC TTP was used as theremote endpoint for the SNP, then the remote endpoint has changed. InFIGS. 38D-38E, there are no facility changes at nodes D, E.

FIGS. 39A-39E are network diagrams of nested MCs with separate VCPs. InFIG. 39A, the facility models are shown for node A. NMC-1-11-1 existswithin MC-1-11, and NMC-1-12-1 exists within MC-1-12. MC-1-11 andMC-1-12 both exist within a common MC-1 terminated MC CTP which existsfor the SNP. MC-1 terminated CTP is cross-connected via a VCP to an MCCTP on the line. This VCP is the local endpoint for the SNP. In FIG.39B, the facility models are shown for node B, and MC-1 iscross-connected through the node B. In FIG. 39C, the facility models areshown for node C. MC-1 is cross-connected to a terminated MC CTP whereit is terminated at the node C. This VCP is the remote endpoint of theSNP. MC-1-11 TTP is terminated, and NMC-1-11-1 is dropped to aterminated NMC CTP. MC-1-12 CTP is cross-connected to another line. InFIG. 39D, the facility models are shown for node D, MC-1-11 iscross-connected through the node D. In FIG. 39E, the facility models areshown for node E, and MC-1-12 is terminated at the node E, along withNMC-1-12-1.

FIGS. 40A-40E are network diagrams of nested MCs with separate VCPs in aredial scenario from the example of FIGS. 39A-39E. In FIG. 40A, at nodeA, a new MC CTP for the SNP is created on a new line. The cross-connectswithin the FCCs for the SNP are changed to use the new MC CTP. The localendpoint for the SNP does not change, and there is no change to anySNCs. In FIG. 40B, the nodes F, G are setup with the associatedfacilities. In FIG. 40C, at node C, a new MC CTP for the SNP is createdon a new line. The cross-connects within the FCCs for the SNP arechanged to use the new MC CTP. The remote endpoint for the SNP does notchange, and there is no change to any SNCs. In FIGS. 40D-40E, there areno facility changes at nodes D, E.

FIG. 41 is a network diagram illustrating relationships between thevarious models. The various models herein model principle MCs asconceptualized in ITU-T G.872. The models allocate bandwidth in physicalmedia (e.g., WSS passband) with a provision for the dead band to accountfor filter roll-off (internal to MC). MCs are terminated by MC TTPobjects at line ports of OADM nodes, giving rise to NMC connectionpoints. By convention, MCId must be consistent within an OMS and MCIdmust be unique for a given line port. These are characterized byFmin/Fmax rather than Fc/Spectral Width to support asymmetricalresizing. A distinct provisionable dead band can be associated with eachof Fmin/Fmax—ENT/ED/DLT-MCCTTP.

The models describe the full network path and spectrum occupied bytraffic signals (including laser tolerance) and may be 1:1 or N:1 withinan MC. The termination points are CMD mux/demux ports. Proposed AIDs caninclude

Line ports—NMCLNCTP-shelf-slot-port-MCId-NMCId; MCId of the parentMCTTP, NMCId is unique within the MCTTP.

Add/drop ports—NMCADCTP-shelf-slot-port-NMCId; Initially, NMCId is 1 andin future may need to support multiple NMCs per CMD port.

There can be a 1:1 OCH-P to NMC relationship. NMC CTPs are implicit andcross-connected by CRS-NMCs and characterized by Fc/Spectral Width.

Traditionally, the WSS pass band and pixel control (spectral)granularity was equivalent for fixed grid technology. As such, thelegacy CHC facility possessed combined attributes for configuringhardware as well as the channel/signal power/loss control function. Forflex capable WSS equipment, multiple traffic signals may be associatedwith a single CHC. Thus it is necessary to introduce a new NMCC (NMCController) facility in order to provision power/loss control parametersfor each channel within the CHC. Additionally, a new SSC (Spectrum ShapeControl) facility will be introduced to tilt/shape the spectrum byprovisioning 6.25 GHz sub-slice attenuation biases. CHC/NMCCs are nolonger static. They are dynamically created/deleted upon CRSprovisioning/de-provisioning. Spectral attributes are equal to theprovisioning of MC and NMC.

The CHC can have the following attributes

-   -   Fmin/Fmax—defines the WSS passband configuration for the channel        (MC)    -   Fmin/Fmax Limit—On certain hardware, defines the limits (set        upon creation) beyond which a CHC can not be resized.    -   Fmin/Fmax Deadband—Models filter roll-off of the CHC and thus        keep-out zones for NMCC provisioning

The NMCC can have the following attributes

-   -   Fc—Center frequency of the NMC    -   Spectral Width—spectral occupancy of the NMC    -   Reference Bandwidth—bandwidth over which power targets and        measurements for optical control are referenced (eg. 50 vs. 12.5        GHz)    -   Control SSC—identifies the SSC object(s) used as basis for        control and typically has 0 bias    -   Control SSC Attenuation—Attenuation (drive) that is being        applied for the control SSC    -   Channel Power—Estimated optical power within the NMCC spectral        width

The SSC (for flex grid only) can have the following attributes

-   -   Bias—used to provision spectral shape—value is relative to        center slice which by definition as 0 bias    -   Atten—total slice attenuation (drive)

It is anticipated that networks will consist of a mix of fixed and flexgrid channels and hardware for an indefinite period of time.Furthermore, since fixed grid channels are a subset of the flex gridobject model, it is proposed to also migrate fixed grid WSSs to the newCHC/NMCC model in order to provide users with a consistent provisioningand troubleshooting procedure for all WSS types. Additionally, softwareefficiencies are realized by applications which can structure databasesand code around a single model. Non-expert users generally do notconcern themselves with the CHC facility. However, it should be notedthat “Channel Degrade” alarms will now be raised against the NMCCfacility instead of the CHC. Troubleshooting will be comparable exceptthat the reference and measured powers are now contained within theNMCC.

FIG. 42 is a network diagram of a new L0 (Layer 0) Control Plane (CP)Flex Grid service provisioning model. Here, a new SNC group concept isintroduced to support a hierarchical MC/NMC model.

In the optical control model, conventionally, the control granularity offixed grid systems was based on the fixed grid channelsthemselves—however, in a flexible grid system there can be a disconnectbetween the control/measurement (WSS/Optical Power Monitor (OPM))granularity of the optical spectrum and the transmitter width (baud) andcenter frequency (Tunable laser source). These two are highly unrelated,the first having to do with the resolution of optical devices and thelatter being a function of the capacity of a modem and the tune-abilityof a laser. One must be able to model the two and still be able tocontrol them.

The result is a unique and powerful two-part approach to modeling foroptical control in the flexible grid: 1) NMCC (NMC Controller object)and 2) SSC (Spectrum Shape Control).

The NMCC is aligned in the spectrum to the NMC and does not necessarilyalign to the control granularity of the WSS or the measurementgranularity of the OPM. This allows the system to provide feedback tothe user/EMS/SDN controller on the basis of the signals that aretraversing the system. The control parameters which have to do with themodem can also be modeled in this object, like width, center frequency,modulation format, capacity, required Signal-to-Noise Ratio (SNR),margin, etc. and performance monitoring and alarming which areassociated with the signal/NMC.

The SSC is the set of objects that align to the attenuation controlgranularity of the WSS. This may also align to the measurementgranularity of the OPM (in which case no intermediate translation isrequired by the controller). In an example embodiment, the SSCgranularity aligns to the MC-TTP granularity, although it could befiner, e.g., MC-TTP with 12.5 GHz granularity and SSC granularity of6.25 GHz, where it is arranged that the 12.5 GHz boundaries align toevery other 6.25 GHz boundary.

The SSC's which are in different MCs have no attenuation controlrelationship to each other and can be set independently. This allowslarge differences which create filter edges to appear—which are modeledas part of the MC deadbands. SSCs in a single MC have a relationship toeach other wherein a maximum delta is enforced in attenuation betweenthem—hence the name—“spectral shape.” This is due to the fact that thereis no guarantee that the NMCs are contained by an integral number ofSSCs, in fact, it is likely that any given SSC may have some portion oftwo NMCs in its frequency range.

By applying a constraint in difference of attenuation between adjacentSSCs, one can ensure a “smooth” shape which does not perturb theadjacent NMCs. This is acceptable since 1) one is trying to compensatesmooth difference due to the transmission system effects such as EDFAripple, SRS, etc. and 2) deltas between NMCs can be applied by adjustingthe transmitter output power or attenuation on MUX ports to createdifferences between adjacent NMCs which will persist through the path inthe network.

In the control plane, conventionally, the SNC was a control plane entitywhich was routed and resulted in a single local OCh. The capability ofFlexible Grid to “pack” channels together into a single MC creates asystem with better spectral efficiency. The SNCG object is added as away for the control plane to understand what the flexible gridconstraints are for a given NMC or set of NMCs, i.e., whether contiguousspectrum in an MC is i) necessary (these NMCs must always be routed inthe same MC, ii) optional (do so when possible, but break them up whenneeded to), iii) constrained (best to be in the same MC, but if indifferent ones, they must be within x GHz of each other (fibredependent), or y ns of relative delay), iv) opportunistic (these NMCsare allowed to be packed into MCs with other MCs on the same path), v)prohibited (this NMC always gets its own MC), etc.

The relationship of these control plane extensions to the above modelhas to do with the “routed entity” being the NMC. The simplestre-routing does not require changing the frequencies of the NMCs beingre-routed. This relies on the possibility of creating identical MC-TTPson the ports which make up the new path. The degree to which this ispossible depends on the network conditions. Finding the next “leastwork” option comes down to satisfying the constraints above.

Networks, such as using Dense Wave Division Multiplexing (DWDM), OpticalTransport Network (OTN), Ethernet, Multiprotocol Label Switching (MPLS),and the like, are deploying control plane systems and methods. Controlplanes provide an automatic allocation of network resources in anend-to-end manner. Example control planes may include AutomaticallySwitched Optical Network (ASON) as defined in ITU-T G.8080/Y.1304,Architecture for the automatically switched optical network (ASON)(February/2012), the contents of which are herein incorporated byreference; Generalized Multi-Protocol Label Switching (GMPLS)Architecture as defined in IETF Request for Comments (RFC): 3945(October/2004) and the like, the contents of which are hereinincorporated by reference; Optical Signaling and Routing Protocol (OSRP)from Ciena Corporation which is an optical signaling and routingprotocol similar to Private Network-to-Network Interface (PNNI) andMulti-Protocol Label Switching (MPLS); or any other type control planefor controlling network elements at multiple layers, and establishingconnections among nodes. Control planes are configured to establishend-to-end signaled connections such as Subnetwork Connections (SNCs) inASON or OSRP and Label Switched Paths (LSPs) in GMPLS and MPLS. Note, asdescribed herein, SNCs and LSPs can generally be referred to as servicesor calls in the control plane. Control planes use the available paths toroute the services and program the underlying hardware accordingly.

In addition to control planes which are distributed, a centralizedmethod of control exists with Software Defined Networking (SDN) whichutilizes a centralized controller. SDN is an emerging framework whichincludes a centralized control plane decoupled from the data plane. SDNprovides the management of network services through abstraction oflower-level functionality. This is done by decoupling the system thatmakes decisions about where traffic is sent (the control plane) from theunderlying systems that forward traffic to the selected destination (thedata plane). Examples of SDN include OpenFlow(www.opennetworking.org/sdn-resources/onf-specifications/openflow/),General Switch Management Protocol (GSMP) defined in RFC 3294 (June2002), and Forwarding and Control Element Separation (ForCES) defined inRFC 5810 (March 2010), the contents of all are incorporated by referenceherein. Note, distributed control planes can be used in conjunction withcentralized controllers in a hybrid deployment.

The various models described herein contemplate use with theaforementioned control planes, SDN, etc.

Example Network

FIG. 43 is a network diagram of an example network 100 with variousinterconnected nodes 102 (illustrated as nodes 102A-102J). The nodes 102are interconnected by a plurality of links 104. The nodes 102communicate with one another over the links 104 through Layer 0 (L0)such as optical wavelengths (DWDM), Layer 1 (L1) such as OTN, Layer 2(L2) such as Ethernet, MPLS, etc., and/or Layer 3 (L3) protocols. Thenodes 102 can be network elements which include a plurality of ingressand egress ports forming the links 104. An example node implementationis illustrated in FIG. 44. The network 100 can include various servicesor calls between the nodes 102 which use the models described herein.Each service or call can be at any of the L0, L1, L2, and/or L3protocols, such as a wavelength, an SNC, an LSP, etc., and each serviceor call is an end-to-end path or an end-to-end signaled path and fromthe view of the client signal contained therein, it is seen as a singlenetwork segment. The nodes 102 can also be referred to interchangeablyas network elements (NEs). The network 100 is illustrated, for example,as an interconnected mesh network, and those of ordinary skill in theart will recognize the network 100 can include other architectures, withadditional nodes 102 or with fewer nodes 102, etc.

The network 100 can include a control plane 106 operating on and/orbetween the nodes 102. The control plane 106 includes software,processes, algorithms, etc. that control configurable features of thenetwork 100, such as automating discovery of the nodes 102, capacity onthe links 104, port availability on the nodes 102, connectivity betweenports; dissemination of topology and bandwidth information between thenodes 102; calculation and creation of paths for calls or services;network level protection and restoration; and the like. In anembodiment, the control plane 106 can utilize ASON, GMPLS, OSRP, MPLS,Open Shortest Path First (OSPF), Intermediate System-Intermediate System(IS-IS), or the like. Those of ordinary skill in the art will recognizethe network 100 and the control plane 106 can utilize any type ofcontrol plane for controlling the nodes 102 and establishing,maintaining, and restoring calls or services between the nodes 102.

An SDN controller 108 can also be communicatively coupled to the network100 through one or more of the nodes 102. SDN is an emerging frameworkwhich includes a centralized control plane decoupled from the dataplane. SDN provides the management of network services throughabstraction of lower-level functionality. This is done by decoupling thesystem that makes decisions about where traffic is sent (the controlplane) from the underlying systems that forward traffic to the selecteddestination (the data plane). SDN works with the SDN controller 108knowing a full network topology through configuration or through the useof a controller-based discovery process in the network 100. The SDNcontroller 108 differs from a management system in that it controls theforwarding behavior of the nodes 102 only, and performs control in realtime or near real time, reacting to changes in services requested,network traffic analysis and network changes such as failure anddegradation. Also, the SDN controller 108 provides a standard northboundinterface to allow applications to access network resource informationand policy-limited control over network behavior or treatment ofapplication traffic. The SDN controller 108 sends commands to each ofthe nodes 102 to control matching of data flows received and actions tobe taken, including any manipulation of packet contents and forwardingto specified egress ports.

Note, the network 100 can use the control plane 106 separately from theSDN controller 108. Conversely, the network 100 can use the SDNcontroller 108 separately from the control plane 106. Also, the controlplane 106 can operate in a hybrid control mode with the SDN controller108. In this scheme, for example, the SDN controller 108 does notnecessarily have a complete view of the network 100. Here, the controlplane 106 can be used to manage services in conjunction with the SDNcontroller 108. The SDN controller 108 can work in conjunction with thecontrol plane 106 in the sense that the SDN controller 108 can make therouting decisions and utilize the control plane 106 for signalingthereof.

In the terminology of ASON and OSRP, sub-network connections (SNC) areend-to-end signaled paths or calls since from the point of view of aclient signal, each is a single network segment. In GMPLS, theconnections are an end-to-end path referred to as LSPs. In SDN, such asin OpenFlow, services are called “flows.” In the various descriptionsherein, reference is made to SNCs for illustration only of an embodimentof the systems and methods. Those of ordinary skill in the art willrecognize that SNCs, LSPs, flows, or any other managed service in thenetwork can be used with the systems and methods described herein forend-to-end paths. Also, as described herein, the term services is usedfor generally describing connections such as SNCs, LSPs, flows, etc. inthe network 100.

Example Network Element/Node

FIG. 44 is a block diagram of an example node 300 for use with thesystems and methods described herein. In an embodiment, the example node300 can be a network element that may consolidate the functionality of aMulti-Service Provisioning Platform (MSPP), Digital Cross-Connect (DCS), Ethernet and/or Optical Transport Network (OTN) switch, WaveDivision Multiplexed (WDM)/ Dense WDM (DWDM) platform, Packet OpticalTransport System (POTS), etc. into a single, high-capacity intelligentswitching system providing Layer 0, 1, 2, and/or 3 consolidation. Inanother embodiment, the node 300 can be any of an OTN Add/DropMultiplexer (ADM), a Multi-Service Provisioning Platform (MSPP), aDigital Cross-Connect (DCS), an optical cross-connect, a POTS, anoptical switch, a router, a switch, a Wavelength Division Multiplexing(WDM) terminal, an access/aggregation device, etc. That is, the node 300can be any digital and/or optical system with ingress and egress digitaland/or optical signals and switching of channels, timeslots, tributaryunits, etc. While the node 300 is generally shown as an optical networkelement, the systems and methods contemplated for use with any switchingfabric, network element, or network based thereon which supports flexgrid services.

In an embodiment, the node 300 includes common equipment 302, one ormore line modules 304, and one or more switch modules 306. The commonequipment 302 can include power; a control module; operations,administration, maintenance, and provisioning (OAM&P) access; userinterface ports; and the like. The common equipment 302 can connect to amanagement system 308 through a data communication network 310 (as wellas a Path Computation Element (PCE), SDN controller, OpenFlowcontroller, etc.). The management system 308 can include a networkmanagement system (NMS), element management system (EMS), or the like.Additionally, the common equipment 302 can include a control planeprocessor, such as a controller 500 illustrated in FIG. 45 configured tooperate the control plane as described herein. The node 300 can includean interface 312 for communicatively coupling the common equipment 302,the line modules 304, and the switch modules 306 to one another. Forexample, the interface 312 can be a backplane, midplane, a bus, opticalor electrical connectors, or the like. The line modules 304 areconfigured to provide ingress and egress to the switch modules 306 andto external connections on the links to/from the node 300. In anembodiment, the line modules 304 can form ingress and egress switcheswith the switch modules 306 as center stage switches for a three-stageswitch, e.g. a three-stage Clos switch. Other configurations and/orarchitectures are also contemplated. The line modules 304 can includeoptical transceivers, such as, for example, 10 Gb/s (OC-192/STM-64,OTU2, ODU2, 10 GbE PHY), 40 Gb/s (OC-768/STM-256, OTU3, ODU3, 40 GbEPHY), 100 Gb/s (OTU4, ODU4, 100 GbE PHY), ODUflex, n×100G frame format(OTUCn), Flexible Ethernet, etc.

Further, the line modules 304 can include a plurality of opticalconnections per module and each module may include a flexible ratesupport for any type of connection. The line modules 304 can includewavelength division multiplexing interfaces, short reach interfaces, andthe like, and can connect to other line modules 304 on remote networkelements, end clients, edge routers, and the like, e.g. formingconnections on the links in the network 100. From a logical perspective,the line modules 304 provide ingress and egress ports to the node 300,and each line module 304 can include one or more physical ports. Theswitch modules 306 are configured to switch channels, timeslots,tributary units, packets, etc. between the line modules 304. Forexample, the switch modules 306 can provide wavelength granularity(Layer 0 switching); OTN granularity; Ethernet granularity; and thelike. Specifically, the switch modules 306 can include Time DivisionMultiplexed (TDM) (i.e., circuit switching) and/or packet switchingengines. Also, the switch modules 306 can provide only opticalswitching, e.g., WSSs.

Those of ordinary skill in the art will recognize the node 300 caninclude other components which are omitted for illustration purposes,and that the systems and methods described herein are contemplated foruse with a plurality of different network elements with the node 300presented as an example type of network element. For example, in anotherembodiment, the node 300 may not include the switch modules 306, butrather have the corresponding functionality in the line modules 304 (orsome equivalent) in a distributed fashion, or omit the functionalityaltogether. For the node 300, other architectures providing ingress,egress, and switching are also contemplated for the systems and methodsdescribed herein. In general, the systems and methods described hereincontemplate use with any network element providing switching ofchannels, timeslots, tributary units, wavelengths, etc. and using thecontrol plane. Furthermore, the node 300 is merely presented as oneexample node 300 for the systems and methods described herein.

Example Controller

FIG. 45 is a block diagram of a controller 500 to provide control planeprocessing and/or operations, administration, maintenance, andprovisioning (OAM&P) for the node 300, and/or to implement a SoftwareDefined Networking (SDN) controller. The controller 500 can be part ofthe common equipment, such as common equipment 302 in the node 300, or astand-alone device communicatively coupled to the node 300 via the DCN310. In a stand-alone configuration, the controller 500 can be an SDNcontroller, an NMS, a PCE, etc. The controller 500 can include aprocessor 502 which is a hardware device for executing softwareinstructions such as operating the control plane. The processor 502 canbe any custom made or commercially available processor, a centralprocessing unit (CPU), an auxiliary processor among several processorsassociated with the controller 500, a semiconductor-based microprocessor(in the form of a microchip or chip set), or generally any device forexecuting software instructions. When the controller 500 is inoperation, the processor 502 is configured to execute software storedwithin the memory, to communicate data to and from the memory, and togenerally control operations of the controller 500 pursuant to thesoftware instructions. The controller 500 can also include a networkinterface 504, a data store 506, memory 508, an I/O interface 510, andthe like, all of which are communicatively coupled to one another and tothe processor 502.

The network interface 504 can be used to enable the controller 500 tocommunicate on the DCN 510, such as to communicate control planeinformation to other controllers, to the management system 308, to thenodes 300, and the like. The data store 506 can be used to store data,such as control plane information, provisioning data, OAM&P data, etc.The data store 506 can include any of volatile memory elements (e.g.,random access memory (RAM, such as DRAM, SRAM, SDRAM, and the like)),nonvolatile memory elements (e.g., ROM, hard drive, flash drive, CDROM,and the like), and combinations thereof. Moreover, the data store 506can incorporate electronic, magnetic, optical, and/or other types ofstorage media. The memory 508 can include any of volatile memoryelements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM,etc.)), nonvolatile memory elements (e.g., ROM, hard drive, flash drive,CDROM, etc.), and combinations thereof. Moreover, the memory 508 mayincorporate electronic, magnetic, optical, and/or other types of storagemedia. The I/O interface 510 includes components for the controller 500to communicate with other devices. Further, the I/O interface 510includes components for the controller 500 to communicate with the othernodes, such as using overhead associated with OTN signals.

In an embodiment, the controller 500 is configured to communicate withother controllers 500 in the network 100 to operate the control planefor control plane signaling. This communication may be either in-band orout-of-band. For SONET networks and similarly for SDH networks, thecontrollers 500 may use standard or extended SONET line (or section)overhead for in-band signaling, such as the Data Communications Channels(DCC). Out-of-band signaling may use an overlaid Internet Protocol (IP)network such as, for example, User Datagram Protocol (UDP) over IP. Inan embodiment, the controllers 500 can include an in-band signalingmechanism utilizing OTN overhead. The General Communication Channels(GCC) defined by ITU-T Recommendation G.709 are in-band side channelsused to carry transmission management and signaling information withinOptical Transport Network elements.

The controller 500 is configured to operate the control plane 106 in thenetwork 100. That is, the controller 500 is configured to implementsoftware, processes, algorithms, etc. that control configurable featuresof the network 100, such as automating discovery of the nodes, capacityon the links, port availability on the nodes, connectivity betweenports; dissemination of topology and bandwidth information between thenodes; path computation and creation for connections; network levelprotection and restoration; and the like. As part of these functions,the controller 500 can include a topology database that maintains thecurrent topology of the network 100 based on control plane signaling(e.g., HELLO messages) and a connection database that maintainsavailable bandwidth on the links 104 again based on the control planesignaling. Again, the control plane is a distributed control plane;thus, a plurality of the controllers 500 can act together to operate thecontrol plane using the control plane signaling to maintain databasesynchronization. In source-based routing, the controller 500 at a sourcenode for a connection is responsible for path computation andestablishing by signaling other controllers 500 in the network 100, suchas through a SETUP message. For example, the source node and itscontroller 500 can signal a path through various techniques such asResource Reservation Protocol-Traffic Engineering (RSVP-TE) (G.7713.2),Private Network-to-Network Interface (PNNI), Constraint-based RoutingLabel Distribution Protocol (CR-LDP), etc. and the path can be signaledas a Designated Transit List (DTL) in PNNI or an Explicit Route Object(ERO) in RSVP-TE/CR-LDP. As described herein, the connection refers to asignaled, end-to-end connection such as an SNC, SNCP, LSP, etc. whichare generally a service. Path computation generally includes determininga path, i.e. traversing the links through the nodes from the originatingnode to the destination node based on a plurality of constraints such asadministrative weights on the links, bandwidth availability on thelinks, etc.

The various models described herein are used by the network 100, thenode 300, and/or the controller 500 to manage and allocate MCs and NMCson the underlying hardware.

End-to-End Service

FIGS. 46A-46F are network diagrams of an end-to-end service in a flexgrid network utilizing the various objects described herein. In FIGS.46A-46C, there is an Optical Channel (OCh) service between nodes 1, 6.FIG. 46A illustrates the models at nodes 1, 2, FIG. 46B illustrates themodels at nodes 3, 4, and FIG. 46C illustrates the models at nodes 5, 6.Each of FIGS. 46A-46C show the NMCs (with corresponding numbers betweeneach node), nested NMCs (with corresponding numbers between each node),MCs (with corresponding numbers between each node), and OMS on eachspan. In FIGS. 46D-46F, a new service is added at node 2 to node 6. FIG.46D illustrates the models at node 2, FIG. 46E illustrates the models atnodes 3, 4, and FIG. 46F illustrates the models at nodes 5, 6.

Those skilled in the art recognize an OCh is formed through variousoptical network components, devices, hardware, etc. that are realized innetwork elements and the like.

It will be appreciated that some embodiments described herein mayinclude one or more generic or specialized processors (“one or moreprocessors”) such as microprocessors; Central Processing Units (CPUs);Digital Signal Processors (DSPs): customized processors such as NetworkProcessors (NPs) or Network Processing Units (NPUs), Graphics ProcessingUnits (GPUs), or the like; Field Programmable Gate Arrays (FPGAs); andthe like along with unique stored program instructions (including bothsoftware and firmware) for control thereof to implement, in conjunctionwith certain non-processor circuits, some, most, or all of the functionsof the methods and/or systems described herein. Alternatively, some orall functions may be implemented by a state machine that has no storedprogram instructions, or in one or more Application Specific IntegratedCircuits (ASICs), in which each function or some combinations of certainof the functions are implemented as custom logic or circuitry. Ofcourse, a combination of the aforementioned approaches may be used. Forsome of the embodiments described herein, a corresponding device inhardware and optionally with software, firmware, and a combinationthereof can be referred to as “circuitry configured or adapted to,”“logic configured or adapted to,” etc. perform a set of operations,steps, methods, processes, algorithms, functions, techniques, etc. ondigital and/or analog signals as described herein for the variousembodiments.

Moreover, some embodiments may include a non-transitorycomputer-readable storage medium having computer readable code storedthereon for programming a computer, server, appliance, device,processor, circuit, etc. each of which may include a processor toperform functions as described and claimed herein. Examples of suchcomputer-readable storage mediums include, but are not limited to, ahard disk, an optical storage device, a magnetic storage device, a ROM(Read Only Memory), a PROM (Programmable Read Only Memory), an EPROM(Erasable Programmable Read Only Memory), an EEPROM (ElectricallyErasable Programmable Read Only Memory), Flash memory, and the like.When stored in the non-transitory computer readable medium, software caninclude instructions executable by a processor or device (e.g., any typeof programmable circuitry or logic) that, in response to such execution,cause a processor or the device to perform a set of operations, steps,methods, processes, algorithms, functions, techniques, etc. as describedherein for the various embodiments.

Although the present disclosure has been illustrated and describedherein with reference to preferred embodiments and specific examplesthereof, it will be readily apparent to those of ordinary skill in theart that other embodiments and examples may perform similar functionsand/or achieve like results. All such equivalent embodiments andexamples are within the spirit and scope of the present disclosure, arecontemplated thereby, and are intended to be covered by the followingclaims.

What is claimed is:
 1. A controller comprising: a processor; and memory storing instructions that, when executed, cause the processor to obtain measurements of optical spectrum from an Optical Power Monitor (OPM) connected to a fiber having thereon, one or more optical signals from one or more optical transmitters, wherein the optical signals are based on a flexible grid, manage the one or more optical signals utilizing a first model and manage attenuation control granularity of a Wavelength Selective Switch (WSS) connected to the fiber utilizing a second model, and configure one or more of the WSS and the one or more optical transmitters based on the first model and the second model.
 2. The controller of claim 1, wherein measurement granularity of the OPM is different from width and center frequency of the one or more optical signals.
 3. The controller of claim 2, wherein the first model aligns to the width and the center frequency of the one or more optical signals, and wherein the second model aligns to the attenuation control granularity of the WSS.
 4. The controller of claim 1, wherein the first model manages control parameters of the one or more optical transmitters.
 5. The controller of claim 4, wherein the control parameters include any of width, center frequency, modulation format, capacity, required Signal-to-Noise Ratio (SNR), and margin.
 6. The controller of claim 1, wherein the second model aligns to a measurement granularity of the OPM and to the attenuation control granularity of the WSS.
 7. The controller of claim 1, wherein the second model includes a plurality of objects corresponding to the optical spectrum and each having a set attenuation of the WSS, and wherein adjacent objects have a limit in a difference of attenuation.
 8. A non-transitory computer-readable storage medium comprising instructions that, when executed, cause a processor to perform the steps of: obtaining measurements of optical spectrum from an Optical Power Monitor (OPM) connected to a fiber having thereon, one or more optical signals from one or more optical transmitters, wherein the optical signals are based on a flexible grid, managing the one or more optical signals utilizing a first model and manage attenuation control granularity of a Wavelength Selective Switch (WSS) connected to the fiber utilizing a second model, and configuring one or more of the WSS and the one or more optical transmitters based on the first model and the second model.
 9. The non-transitory computer-readable storage medium of claim 8, wherein measurement granularity of the OPM is different from width and center frequency of the one or more optical signals.
 10. The non-transitory computer-readable storage medium of claim 8, wherein the first model aligns to the width and the center frequency of the one or more optical signals, and wherein the second model aligns to the attenuation control granularity of the WSS.
 11. The non-transitory computer-readable storage medium of claim 8, wherein the first model manages control parameters of the one or more optical transmitters.
 12. The non-transitory computer-readable storage medium of claim 11, wherein the control parameters include any of width, center frequency, modulation format, capacity, required Signal-to-Noise Ratio (SNR), and margin.
 13. The non-transitory computer-readable storage medium of claim 8, wherein the second model aligns to a measurement granularity of the OPM and to the attenuation control granularity of the WSS.
 14. The non-transitory computer-readable storage medium of claim 8, wherein the second model includes a plurality of objects corresponding to the optical spectrum and each having a set attenuation of the WSS, and wherein adjacent objects have a limit in a difference of attenuation.
 15. A method comprising: obtaining measurements of optical spectrum from an Optical Power Monitor (OPM) connected to a fiber having thereon, one or more optical signals from one or more optical transmitters, wherein the optical signals are based on a flexible grid, managing the one or more optical signals utilizing a first model and manage attenuation control granularity of a Wavelength Selective Switch (WSS) connected to the fiber utilizing a second model, and configuring one or more of the WSS and the one or more optical transmitters based on the first model and the second model.
 16. The method of claim 15, wherein measurement granularity of the OPM is different from width and center frequency of the one or more optical signals.
 17. The method of claim 16, wherein the first model aligns to the width and the center frequency of the one or more optical signals, and wherein the second model aligns to the attenuation control granularity of the WSS.
 18. The method of claim 15, wherein the first model manages control parameters of the one or more optical transmitters.
 19. The method of claim 18, wherein the control parameters include any of width, center frequency, modulation format, capacity, required Signal-to-Noise Ratio (SNR), and margin.
 20. The method of claim 15, wherein the second model includes a plurality of objects corresponding to the optical spectrum and each having a set attenuation of the WSS, and wherein adjacent objects have a limit in a difference of attenuation. 